Re: Shared Memory Sizing

>>>>> "CS" == Curt Sampson <cjs@cynic.net> writes:

CS> For most workloads, in the long run, that will force you to do disk
CS> I/O that you would not have had to do otherwise. A single disk I/O
CS> is far more expensive than hundreds of copies between the OS buffer
CS> cache and postgres' shared memory.

It occurs to me that these two opposing factors could be plotted and
make somewhat of a line each.  The ideal point would be where they
crossed.

Perhaps one day when I've got a few hours I'll copy over my large
dataset to my devel server and try to mimic the load with different
shm sizes...

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Vivek Khera, Ph.D.                Khera Communications, Inc.
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